Abstract

The widely accepted age estimate for the onset of glaciation in the Northern Hemisphere ranges between 2 and 15 million years
ago (Ma). However, recent studies indicate the date for glacial onset may be significantly older. We report the presence of ice-rafted
debris (IRD) in ∼44 to 30 Ma sediments from the Greenland Sea, evidence for glaciation in the North Atlantic during the Middle
Eocene to Early Oligocene. Detailed sedimentological evidence indicates that glaciers extended to sea level in the region, allowing
icebergs to be produced. IRD may have been sourced from tidewater glaciers, small ice caps, and/or a continental ice sheet.